As the wireless communication technology become more and more popular, most of portable electronic devices are generally provided with the function of wireless communication. For instance, users are able to transmit and receive wireless data via mobile devices, such as mobile phones, smart phones, notebooks, personal digital assistants (PDAs), global positioning system (GPS), etc.
An antenna provided in a portable electronic device is mainly used for transmitting or receiving electromagnetic waves. Then, wireless information transmission/receiving is obtained through the propagation of electromagnetic waves in air. The quality of wireless communication is affected by the characteristics of the antenna, such as the resonant frequency (operating frequency) and bandwidth of the antenna, during the use of the antenna.
For the reduction of the volume and weight of the portable electronic device, circuit designers like to integrate antenna inside the portable electronic devices, such as the implementation of the planar F antenna on the printed circuit board. When the antenna is provided on the printed circuit board, it is usually necessary to further provide a clearance region between the antenna and other circuits on the printed circuit board. A clearance region is an area on the circuit board that has no electrical components and no circuit traces printed. This clearance is necessary to avoid the resonant frequency of the antenna being affected by having circuits too close to it. However, due to limited available circuit board area in most compact portable devices, it is quite difficult to print an antenna directly on printed circuit board. The advancement of chip antenna technology makes it a useful compact antenna solution for portable devices. However, the limited bandwidth of most chip antennas becomes a major drawback of it. The major objective of the present invention is to provide a chip antenna for achieving wider bandwidth and easy adjustability while being easily fabricated at a low cost. The antenna characteristics can be easily adjusted and a wider bandwidth can be also obtained to satisfy the need of compact portable devices.